package utils;

import java.security.Key;

import javax.crypto.Cipher;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESedeKeySpec;
import javax.crypto.spec.IvParameterSpec;

/**
 * 3DES加密工具类
 *
 * @author liufeng
 * @date 2012-10-11
 */
public class Des3 {
    // 密钥
    private final static String secretKey = "liuyunqiang@lx100$#365#$" ;
    // 向量
    private final static String iv = "01234567" ;
    // 加解密统一使用的编码方式
    private final static String encoding = "utf-8" ;

    /**
     * 3DES加密
     *
     * @param plainText 普通文本
     * @return
     * @throws Exception
     */
    public static String encode(String plainText) throws Exception {
        Key deskey = null ;
        DESedeKeySpec spec = new DESedeKeySpec(secretKey.getBytes());
        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance( "desede" );
        deskey = keyfactory.generateSecret(spec);

        Cipher cipher = Cipher.getInstance( "desede/CBC/PKCS5Padding" );
        IvParameterSpec ips = new IvParameterSpec(iv.getBytes());
        cipher.init(Cipher.ENCRYPT_MODE, deskey, ips);
        byte [] encryptData = cipher.doFinal(plainText.getBytes(encoding));
        return Base64.encode(encryptData);
    }

    /**
     * 3DES解密
     *
     * @param encryptText 加密文本
     * @return
     * @throws Exception
     */
    public static String decode(String encryptText) throws Exception {
        Key deskey = null ;
        DESedeKeySpec spec = new DESedeKeySpec(secretKey.getBytes());
        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance( "desede" );
        deskey = keyfactory.generateSecret(spec);
        Cipher cipher = Cipher.getInstance( "desede/CBC/PKCS5Padding" );
        IvParameterSpec ips = new IvParameterSpec(iv.getBytes());
        cipher.init(Cipher.DECRYPT_MODE, deskey, ips);

        byte [] decryptData = cipher.doFinal(Base64.decode(encryptText));

        return new String(decryptData, encoding);
    }

    public static void main(String[] args){
        try {
            String str = "eric";
            String dec = Des3.encode(str);
            System.out.println("加密 ###" + dec);
            System.out.println("解密 ###" + Des3.decode("ekVn0V6HXxY="));
        } catch (Exception e) {
            e.printStackTrace();
        }

    }
}